Chp 5: Vertebrate Development

Question 0

Garstang; 1922

Answer 0

Paleogenesis= appearance of ancestral characters in successive generations
Descendant ontogenenies (developments) tend to preserve ancestral ontogenies

Ex: humans do not go through a “fish” stage but they do have pharyngeal slits (not gills) in early embryology, like fish embryos

Question 1

Von Baer; 1828

Thesis:

Answer 1

Embryos develop from general -> specific

Question 2

Acceleration

Answer 2

Heat: environmental, endothermy
Catalyst: enzymes

Question 3

Abbreviation

Answer 3

Neoteny: retain juvenile features (even as adult)

Question 4

Toleration

Answer 4

Behavioral/physiological
A) increase in yolk 
B) viviparity (live birth)
Precocial = well developed
Altricial = helpless
C) parental care

Question 5

Gastrulation

Answer 5

Formation of a gut tube

Question 6

Gastrula

Answer 6

Primitive gut

Question 7

Coelom

Answer 7

Body cavity, lined w/ mesoderm

Question 8

Lumen

Answer 8

Hollow part of an organ

Question 9

1. Chordamesoderm

Answer 9

• becomes notochord

- induces neurulation (form nervous system)

Question 10

2. Epimere

Answer 10

Epi= above
-blocks of tissue = somites
-skin dermis
(Ectoderm forms the epidermis) 
-skeletal muscle
-vertebrae

Question 11

3. Mesomere

Answer 11

• middle

- contributes to kidneys

Question 12

4. Hypomere

Answer 12

Hypo = below

• not segmented splits into 2 layers
• forms lining of coelom = peritoneum
• smooth muscle of gut
• heart and vessels
• limbs
• gonads

Question 13

Ectoderm

Answer 13

• skin epidermis
• nervous system
• sense organs
• pigments

Question 14

Endoderm

Answer 14

• lining

- gut tube (liver, pancreas, lungs)